Guava moth

David from Pakuranga Heights

Dear Neighbours
Regrettably, the dreaded guava moth has become a permanent curse. If you have fruit trees on your property, you'll find the fruit (especially stone fruit like plums, peaches, etc) uneatable. The guava moth will even have a go at citrus.
You'll see a tiny pinhole bored into your fruit where the guava moth has laid its egg. The egg hatches into a grub, about one centimetre long, which destroys the interior of the fruit.

There is no adequate spray to combat this pest (introduced from Australia in recent years and gradually working its way down the North Island, having reached Hamilton so far). Nurseries recommend neem oil but unless you achieve total coverage of the fruit, it does not protect it.

The guava moth spells the end of the backyard orchard. Commercially, when it reaches the Bay of Plenty, it will be devastating to our economy. It has already caused orchardists in the north to remove their feijoas and some people are cutting down their plum trees.

There is one thing we can do to limit this evil pest. Please, please pick up windfall fruit and seal it in a plastic bag before throwing it in the rubbish. A bread bag will do the job nicely. Do not compost this fallen fruit as the grubs will still emerge, pupate and develop into new moths to continue their devastating work.

If you put the fruit into a bucket of water overnight, you will see the grubs when they emerge and they can be tipped down the sink. By destroying what we can of these pests, we can limit the effect of the next generation.
You will find that the fruit which drops off the tree early, with a smudge of ripeness on one side, is fruit already attacked by the guava moth which is in a hurry to emerge and find a convenient place to form its cocoon (from whence it will emerge as a new moth).

The only effective way I know of to limit this pest is the sealed plastic bag method. In this way, we reduce second generation numbers. Please give it a go.

Many thanks, David H.